Process of electrically welding metals



(No Model.)

0. L. OOPFIN. PROCESS OF BLEGTRIGALLY WELDING METALS. No. 437,571.

Patented Sept. 30, 1890.

UNITED STATES PATENT OFFICE.

CHARLES L. COFFIN, OF DETROIT, MICHIGAN.

PROCESS OF ELECTRICALLY WELDING METALS.

SPECIFICATION forming part of Letters Patent No. 437,571, datedSeptember 30, 1890.

Serial No. 347,155. (No model.)

To all whom it may concern.-

Be it known that 1, CHARLES L. COFFIN, of Detroit, in the county ofWVayne and State of Michigan, have invented a new and useful Improvementin Process of Electric Welding and Metal-IVorking, of which thefollowing is a specification.

My invention consists of an improved process of electric welding andmetal-working, hereinafter fully described and claimed.

The drawings represent apparatus by which my invention may be practiced.Figures 1, 2, and 3 are perspectives, and Figs. 4 and 5 are'partialelevations.

In Fig. 1, T represents a table, upon which are mounted two posts A andA, the upper part of post A being made movable and controlled by ascrew-shaft E, having a crank F. I represents insulation in all thefigures. C C represent clamps supported on posts A and A, but insulatedtherefrom, the upper half of each clamp being movable by means of awinch G and sliding block H or in any other convenient manner. Brepresents a post, movably mounted 011 table T, carrying an anvil-blockD, preterably of carbon, which is movable vertically by a screw-shaft L.B represents a post secured to but insulated from table T, which carriesa vertically-sliding head K, at the lower end of which is a conductor D,(preferably of carbon.) The post B is connected by the conductor Y withone pole only of a generator, and the clamps C C are connected by abranched conductor Y, in which there may be resistance-switches S toequalize the resistance of the branches with the other pole of saidgenerator. M M represent the articles to be welded together, which areclamped in the clamps C, and are supported by the anvil D, either incontact, as shown in Figs. 1, 3, and 5, or separated,as shown in Fig. 4.

In the operation of this apparatus, the articles being clamped, as shownin the figures, the conductor D is brought down to make contact with thearticles M M, and a heatingcurrent is then passed through the conductorsY Y, traversing, the articles M M and passing out through conductor D,or vice versa, by which the articles M M are heated at their point ofcontact with the conductor D, when they may be pressed together by thewinch E F to form the weld, which may be completed by hammering,rolling, &c.

In Fig. conductor D and anvil D are both represented by one pair oftongs, which are clamped on the article M at the point where it isdesired to heat said article, and the clamps C C are connected with thearticle M at each side of this point, being both connected by a branchedconductor Y with one pole of a generator, and the tongs D beingconnected by the conductor Y with the other pole of said generator.

In Fig. 4: the arrangement is substantially the same as Fig. 1, theconductor D being raised and lowered by an eccentric K, and a similareccentric being substituted for the shaft L to lower and raise the anvilD. In this figure the articles M M pass through hollow magnets N N andare not in contact, one being connected by the conductorY with one poleonly of a generator, and the conductor D being connected by theconductor Y with the other pole of the generator, one of the articles Mbeing directly heated by the current and the other heated by radiation.

In Fig. 3 the apparatus of Fig. 4 is shown as applied to welding a hoop,which is held in the upper clamp 0, provided with the eccentric K, andthe clamps C C, which are connected with the branched conductor Y, arein this case connected with the hoop on opposite sides of the joint.

In Fig. 5 the mechanism of Figs. 3 and 4 is indicated as applied tomaking a lap-joint between the articles M M.

A description of the operation of Fig.1 applies to all the figures.

\Vhat I claim as my invention, and desire to secure by Letters Patent,is

The process herein described of welding metals electrically, whichconsists in bringing the parts to be welded in contact with an anvil,and a conductor, which is connected with one pole of a generator,connecting said articles with the other pole of said generator only,passing a heating-current through the articles and conductor, andpressing the articles together and forming the weld while in contactwith said conductor, substantially as set forth.

CHARLES L. COFFIN.

Witnesses:

CYRUS E. Lornnor, GERTRUDE H. ANDERSON.

